/Engine/Source/Runtime/MeshDescription/Public/MeshDescriptionBase.h
Returns the polygons associated with the given polygon group
void GetPolygonGroupPolygons ( [FPolygonGroupID](API\Runtime\MeshDescription\FPolygonGroupID) PolygonGroupID, [TArray](API\Runtime\Core\Containers\TArray)< [FPolygonID](API\Runtime\MeshDescription\FPolygonID) > & OutPolygonIDs ) const